The present invention relates to a gyroscopic force measuring cell having a frame with a gyroscope suspended force-free therein with an inner and outer gimbal such that a force incident at the rotational axis of the gyroscope and generating a torque produces precessional motion about the precessional axis having a velocity which is proportional to the force and which serves as a measurement thereof.
A gyroscopic force measuring cell wherein the precessional motion generated about the vertical axis of the gyroscope by a force to be measured is employed for measuring the force is described in German OS 29 19 702, for example. The force to be measured is either directly or indirectly incident at the non-co-precessing portion of a suspension of the gyroscopic force measuring cell rotatably seated about the vertical axis. In this known force measuring cell, the co-precessing portion of the suspension is hinged by means of bands to the respective inner and outer gyroscope gimbals. In one embodiment, the bands connected to the inner gyroscope gimbal intersect the bands connected to the outer gimbal.
This conventional arrangement is unstable and is susceptible to relatively rapid deterioration of the overall measuring system, thus leading to measuring errors due to the influence of external forces, particularly cross forces. This conventional device is moreover sensitive to incident loads which are not precisely coaxial relative to the precessional axis. The unequal elongation of the bands due to temperature effects causes migration of the rotational axis of the rotatable bearing out of alignment with the precessional axis, thus resulting in asymmetrical loads and consequently also leading to measurement errors. Additionally, an inclination of the gyroscope rotational axis causes the same disadvantageous consequences, even if such inclination is very small.